A wide variety of absorbent catamenial tampons have long been known in the art. Most currently commercially available tampons are made from a tampon pledget which has been compressed into a substantially cylindrical form. Tampon pledgets of a variety of types and constructions have been described in the art. Prior to compression, the pledget may be rolled, spirally wound, folded, or assembled as a rectangular pad of absorbent material. Tampons made from a generally rectangular pledget of absorbent material have been popular and successful in the market.
The absorbent catamenial tampons now in use typically comprise absorbent members which are compressed to a generally cylindrical form about three-eighths to one-half inch (about 1.0 cm to 1.3 cm) in diameter and from about 2 cm to 7 cm in length. In order to provide the desired total absorbency, these absorbent members are usually formed from batts larger in size than the vaginal orifice, which are then compressed to the size (with a corresponding increase in rigidity) indicated above in order to facilitate insertion. As fluid is absorbed, these compressed tampons are expected to re-expand toward their original pre-compressed size, and to eventually become large enough to effectively cover the vaginal cavity against fluid leakage or bypass. While it has been found that these compressed tampons perform their intended function tolerably well, even the best of them do not always re-expand sufficiently, or fast enough, to provide good coverage against leakage.
It has been long recognized that the internal vaginal cavity in its normal collapsed state is of much wider dimension in its transverse plane than in its vertical plane. It is equally well known that the minimum dimension of the vagina is near the introitus while the maximum dimension is near the cervix. It is desirable, therefore, when considering a tampon for catamenial use, to provide a structure which is in its initial state is of a size and/or shape to pass through the vaginal orifice without discomfort, and when once inside the vaginal cavity and beyond the restrictions of the orifice may be expanded, particularly in the lateral direction, to contact substantially all of surface of the vaginal walls from one side to the other in the vaginal cavity to prevent early bypass of the menstrual discharges from the cervix.
The prior art has long recognized various mechanisms by which tampons might fail to deliver superior performance. One such mechanism is often referred to in the art as “bypass” failure. Bypass failure occurs when the menses travels along the length of the vagina without contacting the tampon, i.e. the tampon fails to intercept the flowing menses.
A compressed tampon, to perform well, should re-expand as quickly and fully as possible and should be in a form to provide the best possible anatomical fit. Nevertheless, these needs are not always consistent with the desire to provide a tampon which is sufficiently small and rigid enough to facilitate an easy insertion. Additionally, even after use, the tampon should be as comfortable as possible to remove from the vaginal cavity. Prior art tampons, therefore, attempted to balance these design objectives as best as possible, often having to trade some performance with respect to one objective for improved performance with respect to another.
Typical currently marketed tampons will usually expand in use to a width dimension in a range from about 15 mm to about 26 mm. This may be smaller than the width of the vaginal cavity in its collapsed state. In particular, because the maximum width dimension of the vagina is near the cervix, tampons which are placed within the upper third section of the vaginal canal (which is where tampons are often placed) may not always expand sufficiently, particularly in the width direction, to provide superior coverage. Additionally, typical currently marketed tampons may not even be able to achieve the width dimensions given above when under pressure (such as by the pressure of the vagina during use). Another consideration is the rate and nature of tampon re-expansion which may not always be optimal in currently available tampons.
It is, therefore, desirable to provide a tampon with improved expansion characteristics, particularly in the width dimension. Such a tampon should not introduce new drawbacks, such as a decreased ability to comfortably remove the tampon. Ideally, such a tampon should be able to be manufactured out of materials similar to those currently used for tampons. These materials have the advantages of a proven record of suitability for human use, acceptable cost, and the ability to be manufactured into tampons without undue modifications to current commercially available manufacturing equipment.
It has been found that even the best-designed currently available tampons do not always re-expand as designed in a manner to completely eliminate leakage. Therefore, it is desirable to provide a tampon, which in addition to improved expansion characteristics, is provided with an improved leakage protection mechanism which is independent of tampon re-expansion. Ideally, such tampons would also be provided with an improved applicator to enhance to likelihood that the benefits of the tampon will be achieved by a majority of users.